Term
| How thick the the cell membrane? Organelle membranes? |
|
Definition
|
|
Term
| In a fatty acid where is the site of carbon number 1? |
|
Definition
|
|
Term
| What is the typical length of the acyl chain in fatty acids? |
|
Definition
| 14-20 carbons, usually even numbers |
|
|
Term
| What differentiates saturated fatty acids from unsaturated fatty acids? (3 things) |
|
Definition
1) double bond usually at position 9 (almost always cis)
2) Saturated has strong interactions between parallel chains
3) Saturated has higher MP |
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|
Term
| What is the storage form of fatty acids? How is this achieved? |
|
Definition
Triacylgrlycerols
Achieved by neutralizing charge |
|
|
Term
| What is the simplest glycerophospholipid? Describe it. |
|
Definition
Phophatidic acid
Glycerol molecule with an esterified phosphate at an alpha carbon |
|
|
Term
| What fatty acid is found on the inner mitochondrial membrane? |
|
Definition
| Phosphatidyl glycerol; cardiolipipin; same as phosphatidic acid but with a second phosphate head group |
|
|
Term
| Where are plasmalogens found and what makes them different? |
|
Definition
Found in heart and brain
Contains an a,B unsaturated ether instead of ester at C1 |
|
|
Term
| What are the three sphingolipids? |
|
Definition
| Sphingosine, ceramides, and sphingomyelins |
|
|
Term
| What occurs in Gaucher's disease? What kind of disease is it? |
|
Definition
| A deficiency in glucocerebrosidase; autosomal recessive chromosome 1; most common lysosomal storage disorder |
|
|
Term
| What is treatment for Gaucher's disease? |
|
Definition
Imiglucerase (generic)
Cerezyme (brand) |
|
|
Term
| What is the most common sterol? Which membrane is it almost exclusively found in? |
|
Definition
| cholesterol; plasma membrane |
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|
Term
| How can it be determined what whether a cell contains certain peripheral or integral proteins? |
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Definition
| Peripheral proteins are released by salt solutions of different ionic strengths or extremes of pH; integral proteins are released by detergents or organic solvents |
|
|
Term
| A lipid that contains both hydrophobic and hydrophilic regions are called? |
|
Definition
|
|
Term
|
Definition
| Spherical vesicle with a phospholipid bilayer |
|
|
Term
| What allows Doxil's half life to be extended and what does it treat? |
|
Definition
| Treats sarcoma lesions and cancer tumors; stealth liposomes increase half life |
|
|
Term
| What model of a cell membrane was proposed in 1972 and who proposed it? |
|
Definition
| Singer and Nicolson's Fluid Mosaic Model |
|
|
Term
| Explain why temperatures above Tm cases a gel-like phase? |
|
Definition
| Because cholesterol becomes more rigid than the fatty acid tails of the phospholipids, thus limiting disorder/fluidity |
|
|
Term
| What happens to Tm when high cholesterol:phospholipid ratios are established? |
|
Definition
|
|
Term
| When does cholesterol interfere with the interaction of hydrocarbon tails of fatty acids and increase fluidity? |
|
Definition
|
|
Term
| What is the function of flippase and floppase? |
|
Definition
| Flippase flips the bilayer lipid from extracellular to intracellular and floppase is vice versa. |
|
|
Term
| Where is the choline containing phospholipids main found? |
|
Definition
| Outer leaflet of cell membrane |
|
|
Term
| Which lipids are mainly found in the inner leaflet of the cell membrane? |
|
Definition
| phosphatidylserine and phosphatidylethanolamine |
|
|
Term
| What is present in human erythrocyte membranes in much larger amounts than in rat liver membranes? |
|
Definition
|
|
Term
| Which two proteins are found mostly in the inner leaflet? Outer leaflet? |
|
Definition
Inner: PE and PS
Outer: PC and SP |
|
|
Term
| Glycolipids are only found where? |
|
Definition
|
|
Term
| What are discrete regions enriched in glycolipids and cholesterol; more rigid and thicker than surrounding membrane? |
|
Definition
|
|
Term
| What typically collects toward the inner leaflet of a lipid raft and is believed to play a part in signal transudction? |
|
Definition
|
|
Term
| What proteins play an important role in maintenance of biconcave shape in erythrocytes? (two things) |
|
Definition
| Spectrin, which is bound to Ankyrin |
|
|
Term
| Explain the variables in Frick's Law and what it is good at predicting. |
|
Definition
J = -D(dC/dx)
J = flux (molecules)
D = diffusion coeff.
dc/dx = change in concentration
Predicts any above variable in passive diffusion only. |
|
|
Term
| What determines hydrophobic nature of transporter proteins in a membrane? |
|
Definition
|
|
Term
| What is the difference in the curves of facilitated and passive diffusion in relation to rate of transport vs. concentration difference? |
|
Definition
| Facilitated diffusion raises rapidly then sharply evens out becoming linear while passive diffusion's rate of transport increases linearly with concentration difference. |
|
|
Term
| What is the main difference between pore and channel proteins? |
|
Definition
| specificity; channel proteins are more substrate specific |
|
|
Term
| How much faster is facilitated transport than passive diffusion? |
|
Definition
|
|
Term
| What is an example of an alpha type channel? Beta barrel channel? |
|
Definition
Aquaporins - alpha
OM of Mitochondria - beta barrel |
|
|
Term
| What are two examples of passive mediated transport systems? |
|
Definition
Glucose transporter (GLUT 1-7; symport)
Cl and HCO3 (antiport) |
|
|
Term
| What are characteristics of integral proteins? (two things) |
|
Definition
| Membrane spanning and 12 alpha helices woven into membrane. |
|
|
Term
| What is the protein encoded by the cystic fibrosis gene? What is unique among channels and ABC transporters? |
|
Definition
Cystic Fibrosis Transmembrane Conductance Regulator (CFTR)
R-domain |
|
|
Term
| What is an antibiotic that acts as an ion pore? |
|
Definition
|
|
Term
| What is created by bacteria and when secreted, often times creates a pore in a lipid bilayer? |
|
Definition
|
|
Term
| What drug inhibits an enzyme involved in the synthesis of bacterial walls? |
|
Definition
|
|
Term
| What is the role of Aspirin? |
|
Definition
| Inhibit (acetylate) prostaglandin synthase (cyclooxygenase) |
|
|
Term
| What is the role of Amanitin? |
|
Definition
| Inhibits RNA polymerase II; found in a particular mushroom |
|
|
Term
| What is a diagnostic for muscular dystrophy? |
|
Definition
| High levels of muscle creatine kinase |
|
|
Term
| What is the short definition of an enzyme and what does it exist as? |
|
Definition
| A biological catalyst; exists as protein, sometimes RNA |
|
|
Term
| On average how much do enzymes speed up reactions? |
|
Definition
|
|
Term
| What is the turnover number of enzymes (how quickly do they work)? |
|
Definition
| 20 per second (20 products catalyzed per second) |
|
|
Term
| What is a cofactor? What is a prosthetic group? |
|
Definition
cofactor: a small molecule required for activity
prosthetic group: a cofactor that is very tightly bound to the enzyme |
|
|
Term
| What is an apoenzyme? What is a holoenzyme? |
|
Definition
Apoenzyme: an enzyme minus its prosthetic group (inactive)
Holoenzyme: enzyme containing its prosthetic group |
|
|
Term
| Describe what enzymes are involved in oxidation-reduction reactions and give an example. |
|
Definition
Oxidoreductase
Alcohol Dehydrogenase
NAD+ needed |
|
|
Term
| Which enzymes are involved in the transfer of groups such as PO4? |
|
Definition
Transferase
Hexokinase
ATP needed |
|
|
Term
| Which enzymes are involved in the addition and cleavage of water? |
|
Definition
Hydrolase
Glucose-6-phosphatase
H2O needed |
|
|
Term
| What enzyme is involved in cleavage by elimination? |
|
Definition
Lyase
Aspartate ammonia lyase (aspartase) |
|
|
Term
| What enzyme is involved in converting UDP-galactose to UDP-glucose? |
|
Definition
Isomerase
UDP-galactose 4-epimerase |
|
|
Term
| Which enzymes are involved in coupling two molecules (ATP hydrolysis)? |
|
Definition
Ligase
Aminoacyl-tRNA synthetase
Lucine + ATP needed |
|
|
Term
| What is the zero order rate law, integrated rate law, units of K, and half life? |
|
Definition
-dA/dt = k
A=Ao-kt
M/s
t = Ao/2k |
|
|
Term
| What is the first order rate law, integrated rate law, units of K, and half life? |
|
Definition
-dA/dt = kA
A = Ao*e^-kt
1/s
t = ln(2)/k |
|
|
Term
| What is the Michaelis-Menten equation? |
|
Definition
| vo = ( Vmax*[S] )/( Km + [S] ) |
|
|
Term
| Given a plot of velocity vs. [S] how can one find Vmax? |
|
Definition
| Vmax is the asymptote of the curve |
|
|
Term
| How can one determine Km given a plot of v vs. [S]? |
|
Definition
| Km is the point on the x axis where Vmax is divided by 2. |
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